The use of search engines can leave a user with an overwhelming list of results for any given query. Some systems attempt to order the documents returned in relative order based on, for example, words in the title or number of clicks from previous searches. In the case of shopping searches, related items may be presented based on the returned documents, such as, category or price. Because the quality of the returned documents may be inconsistent, the related items may include unexpected results. For example, a shopping search on a popular search engine for the word “rose” may return documents from audio CDs to gaming consoles, with no documents for flowers even presented in the top 10 results. Shopping categories presented may range from earrings to history books.
When sorting for a particular characteristic, such as price, excessive boost given to that characteristic may cause that feature to be dominant over another at the cost of losing relevance altogether. For example, a request to order “GPS” search results by price may result in an inexpensive bracket for mounting a GPS being shown first, when that is almost certainly not what a user was looking for.